QUICK NITROGEN TESTS FOR USE ON BEAN AND SWEET CORN CROPS IN QUEBEC (CANADA)
Experiments and a survey were conducted to assess the potential of quick tests for evaluation of N status of bean and sweet corn crops grown for processing in Quebec (Canada). Merckoquant test strips and the Nitracheck reflectometer were used for NO3-N quantification. Nitrogen fertilization was applied at 5 rates. Nmin contents at sowing were relatively low both in commercial fields or experimental plots. NO3 thresholds in sap at 3 weeks after sowing could be used as a way to quantify topdressing N applications but this NO3 content can vary from year to year. Chlorophyll-meter readings were not correlated to N application at a crop development stage early enough to adjust side dressed N applications. Bean was shown to leave a higher Nmin after harvest than sweet corn and may produce a higher N loss to the environment.
Tremblay, N., Dextraze, L., Roy, G., Bélec, C. and Charbonneau, F. (1999). QUICK NITROGEN TESTS FOR USE ON BEAN AND SWEET CORN CROPS IN QUEBEC (CANADA). Acta Hortic. 506, 141-146
Diagnosis, Merckoquant test strip, Nitrate, Phaseolus vulgaris, Zea mays